Nickel is a component of hydrogenase in rhizobium japonicumt. Cupriavidus metallidurans ch34 is able to grow autotrophically as a hydrogenoxidizing bacterium and produces nickeldependent hydrogenases, even under heterotrophic conditions. An nadphdependent hydrogenase was overproduced by almost an order of magnitude in a hyperthermophilic microorganism. Hydrogenases catalyze the reversible oxidation of hydrogen and allow bacteria to use hydrogen as an energy source for their growth. Nife hydrogenase is a type of hydrogenase, which is an oxidative enzyme that reversibly convert molecular hydrogen in prokaryotes including bacteria and archaea.
It is proposed that nickel is ligated solely by amino acid residues of the. Nickeldependent reconstitution of hydrogenase apoprotein. Synthesis of nickeliron hydrogenase in cupriavidus. Read nickeldependent reconstitution of hydrogenase apoprotein in bradyrhizobium japonicum hup c mutants and direct evidence for a nickel metabolism locus involved in nickel incorporation into the enzyme, archives of microbiology on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Fefe and nifehydrogenase diversity, mechanism, and maturation. In vivo and in vitro nickeldependent processing of the nife hydrogenase in azotobacter vinelandii. Addition of nickel to such cells increased hydrogenase activities fivefold over 2 h. Cells grown heterotrophically with fructose and glycerol revealed a specific activity of soluble and membranebound hydrogenase which was severalfold higher than the normal autotrophic level.
Hydrogenases are enzymes that catalyze the reversible activation of hydrogen and which occur widely in prokaryotes as well as in some eukaryotes. Hydrogenases are subclassified into three different types based on the active site metal content. Summary hydrogenase activity and other hydrogenase. Fefe hydrogenases contain a dinuclear fe active site along with fes clusters 77. Nickeliron hydrogenase top, ironiron hydrogenase center, and iron hydrogenase bottom. High xray dose structure of anaerobically purified dm.
Characterization of helicobacter pylori nickel metabolism. A relevant source of this element is the process of biological nitrogen fixation, in which at least. Most of these species are microbes and their ability to use h 2 as a metabolite arises from the expression of h 2 metalloenzymes known as hydrogenases. In nearly all of the synthetic nir models reported so far, the hydride ligand is either displaced toward fe, or terminally bound to fe. The increase in the first hour did not require transcription and translation and correlated with processing of the large form of the alpha subunit prealpha to the small form alpha resembling the alpha subunit from the purified enzyme. The expression of hydrogenase genes was investigated in d. Complex transcriptional control links nikabcdedependent. In the absence of nickel, both jh103k10 and jh103 synthesized high levels of. Here, the authors show that lactate racemase represents a new type of nickeldependent enzyme.
Chan kh, li t, wong co, wong kb 2012 structural basis for gtpdependent dimerization. Formal redox states for iron and nickel are indicated and bridging ligand identities are. Nickel also relieved edta inhibition of methylene bluedependent hup activity, suggesting that nickel is involved directly with the h2activating hydrogenase enzyme. Cells limited for nickel exhibited low hydrogenase activities and contained an apparently large form of. Pmc free article menon nk, chatelus cy, dervartanian m, wendt jc, shanmugam kt, peck hd, jr, przybyla ae. Formal redox states for iron and nickel are indicated and bridging ligand identities are proposed in parentheses when known and brackets when speculative. Pdf the advancements of quantum chemical methods and. Nifehydrogenase activity journal of biological chemistry. Siegbahn 1, shilu chen 2 and rongzhen liao 3 1 department of organic chemistry, arrhenius laboratory, stockholm university, se10691 stockholm, sweden 2 school of chemistry and chemical engineering, beijing institute of technology, beijing 81, china 3 school of chemistry and chemical engineering, huazhong. Cyanobacteria and alga are capable of anaerobically metabolizing carbohydrates to provide reducing equivalents for hydrogenase and may do so in either lightdependent or dark reactions 33, 34. The most abundant hydrogenases contain a nife active site. Nickel deficiency gives rise to the defective hydrogenase. Expression of the nifadependent hupsl promoter varied depending on the genetic background, while the hyp operon, which is.
Nickel is a component of hydrogenase in rhizobium japonicum article pdf available in journal of bacteriology 1591. Cells were grown in 63ni and the hydrogenase was subsequently. Lactate racemase is an enzyme that interconverts the l and d isomers of the common metabolite lactate. Nickel serves as a substrate recognition motif for the. Research article open access dual role of hupf in the. Normally, it is stable and must be coaxed with powerful catalysts to enter into chemical reactions. Without the presence of ni, urea conversion is impossible.
Nickel also relieved edtainhibition ofmethylene bluedependent hup activity, suggesting that nickel is involved directly with the h2activating hydrogenase enzyme. In recent years research has focused on biological mechanisms for hydrogen production and specifically on hydrogenases, the. The nickeldependent chemolithoautotrophic growth of alcaligenes eutrophus is apparently due to a requirement of nickel for active hydrogenase formation. Supporting this hypothesis, a study of the oxygen tolerance and kmh2 dependence on ph, temperature, and. Hydrogenases are enzymes that catalyze the reversible activation of hydrogen and which occur.
It has been estimated that 99% of all organisms utilize dihydrogen, h 2. The addition of nickel to the growth medium specifically restores the intracellular nickel concentration and the hydrogenase activity in. The hydrogenase gene expression is also regulated by the level of o 2 present in the cell environment. Nickeldependent reconstitution of hydrogenase apoprotein in bradyrhizobium japonicum hup c mutants and direct evidence for a nickel metabolism locus involved in nickel incorporation into the enzyme. Sharon mendel, colin robinson, in the enzymes, 2007. Western blot analysis ofthe hydrogenase a subunit in wholecell lysates from nickelsufficient lane 1, nickelsupplementedlanes2to 8, andnickellimited lane9cultures. Effects of ntaand nickel on the hydrogenase a subunit froma. To examine the possibility of increasing the photobiological production of hydrogen within cyanobacterial cultures, we expressed the fefe hydrogenase, hyda, from clostridium acetobutylicum in the non. Adding nickel or edtato either whole cells or crude extracts after derepression did not affect the hydrogenase activity. Hydrogen is produced in soils as a result of different metabolic routes.
Maturation of the enzyme involves cleavage of a putative nterminal signal sequence in the beta subunit and removal of 15 amino acids from the c terminus of the alpha subunit. Production and application of a soluble hydrogenase from. Interestingly, there is a strong link between nickel pools in plants e. Loss of its two native plasmids resulted in inability of the resulting strain ae104 to synthesize the hydrogenases and to grow autotrophically in phosphatepoor, trisbuffered mineral salts medium tmm. There are various types of hydrogenases, but all of them seem to contain at least one ironsulphur cluster. In vivo and in vitro nickeldependent processing of the. Nickeldependent restoration of hydrogenase activity and large subunit processing in the nik mutant. Hydrogen uptake hydrogenase in helicobacter pylori fems. Unfortunately, current industrial methods for hydrogen production are expensive or environmentally unfriendly. Hydrogenases can be divided into two major superfamilies. The role of cytochrome c 3 in the mechanism is also discussed. Structural basis of a ni acquisition cycle for nife hydrogenase by. The properties and roles of some nimetabolizing hydrogenase accessory proteins have similarities to the maturation proteins needed for other nickel containing enzymes. It is likely that a nickel ion is loaded to an extra metal binding site at the dimeric interface of gtpbound hypb and transferred to the hydrogenase upon gtp hydrolysis.
Homologous overproduction of an affinitytagged hydrogenase was achieved. Several of the nidependent enzymes we describe require auxiliary. The first structure of a nifese hydrogenase showed the protein in the reduced state, which revealed an open coordination site between nickel and iron presumably containing a hydride ligand, which is invisible in crystallography as in the standard hydrogenases. The double mutant required 10 to 20 times more nickel ni to achieve near parental strain levels of hydrogenase activity. Synthesis of the hydrogenase is nickeldependen t, and is stimulated by carbon dioxide as electron sink during co 2fixation.
The bimetallic cofactor of nifesehydrogenase is composed of ni and fe. Native and mutant forms of hydrogenase can now be generated for in vitro biochemical analyses and bioenergy systems. These results suggest that the nickeldependent regulation of p nik is strongly correlated with the synthesis of active hydrogenase at limiting nickel concentrations and raise the question of whether nikr activity is altered under these conditions as a result of competition for available nickel ions. Volume 242, number 1, 48 feb 06600 december 1988 a pulsed epr study of redoxdependent hyperfine interactions for the nickel centre of desulfovibrio gigas hydrogenase alan chapman, richard cammack, claude e. Here, the two proteins were purified and characterized. The purified nickeliron hydrogenase performed tcvii reduction and precipitation at high rates. These series of genetic and biochemical approaches demonstrated that the periplasmic nickeliron hydrogenase of sulfatereducing bacteria functions as a tcvii reductase. The nife hydrogenase h2ase has been characterized in the nir state with a hydride bridging between fe and ni but displaced toward the ni. Hydrogenases from methanogenic archaea, nickel, a novel. Lactate racemase is a nickeldependent enzyme activated by. Hypa bound two ni2 ions per dimer with positive cooperativity hill coef. They catalyze various reactions by using active sites of diverse complexities, such as mononuclear nickel in ni. Previous studies demonstrated that two accessory proteins, hypa and hypb, play a role in nickeldependent maturation of both hydrogenase and urease in helicobacter pylori.
Recently, a structural and functional nifeh2ase mimic nat. H2 oxidation in azotobacter vinelandii is catalyzed by a membranebound, alpha beta dimeric nife hydrogenase. Nickel nutrition in plants 2 nickel works as a cofactor to enable urease to catalyze the conversion of urea into the ammonium ion, which plants can use as a source of n. Nickeldependent reconstitution of hydrogenase apoprotein in bradyrhizobium japonicum hupc mutants and direct evidence for a nickel metabolism locus involved in nickel incorporation into the enzyme. Under conditions of nickel limitation, some methanogens synthesize a nickelindependent fehydrogenase instead of f 420reducing nifehydrogenase and by that reduce their nickel requirement. Synthesis of the hydrogenase is nickel dependen t, and is stimulated by carbon dioxide as electron sink during co 2fixation. Wildtype b178 wt and its derivatives nb01 nik, hyd720k. The catalytic site on the enzyme provides simple hydrogenmetabolizing microorganisms a redox mechanism by which to store and utilize energy via the reaction shown in figure 1. Pdf involvement of the groe chaperonins in the nickel. The fehydrogenase harbors a unique ironguanylylpyridinol cofactor fegp cofactor, in which a lowspin iron is ligated by two co, one coch 2.
Pdf nickel is a component of hydrogenase in rhizobium. The properties and roles of some nimetabolizing hydrogenase accessory proteins have similarities to the maturation proteins needed for other nickelcontaining enzymes. Engineeringhyperthermophilicarchaeon pyrococcusfuriosus. A double mutant jh103k10 was created from hydrogenase constitutive mutant jh103 by replacement of a chromosomal 0. Crystal structure of the nickeliron hydrogenase from. Rewiring hydrogenasedependent redox circuits in cyanobacteria. The fddependent fefehydrogenases are widespread in anaerobic bacteria. The increase in the first hour did not require transcription and translation and correlated with processing of the large form of the alpha subunit prealpha to the small form alpha resembling. But when mixed with oxygen, a tiny spark will set off an explosive chain reaction. Nickel requirement for active hydrogenase formation in. These results suggest that the nickel dependent regulation of p nik is strongly correlated with the synthesis of active hydrogenase at limiting nickel concentrations and raise the question of whether nikr activity is altered under these conditions as a result of competition for available nickel ions. The nife and nifese hydrogenases are heterodimer that consist of a small subunit that contains a signal peptide and a large subunit.
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